The present invention generally relates to devices for personal airway humidification. More particularly, this invention relates to a personal airway humidification apparatus adapted to provide humidified air, oxygen-enriched air, or combination thereof to a patient.
It is a well-known and acknowledged concept that breathing plays a role in systemic fluid balance, chemical balance, and temperature control in a patient's body. Personal humidification devices are commonly utilized to provide a water saturated air to a patient in order to treat a variety of conditions. The literature involving the medical use of gaseous water and findings relating to such uses is voluminous. In addition to the humidity level of the air, the oxygen content is also known to be important to the treatment of patients. As an example, oxygen-enriched air is commonly used on patients for respiratory treatment. Ideally, the water saturated air has 100 percent water saturation, as lower saturation amounts may cause dehydration rather than hydration, and is at an elevated temperature adequate to promote mucus mobility (i.e., reduce mucus retention).
A variety of devices have been developed and manufactured for use as personal humidification devices, with the object of promoting pulmonary hygiene and bronchial dilation in a patient. Personal humidification devices deliver humidified air directly to the respiratory airway of patients, and as such do not include room humidifiers. Related devices include devices disclosed in U.S. Pat. No. 4,773,410, devices manufactured by the OECO Corporation and Gulfstream, various aerosol-producing or nebulization devices, CPAP and BIPAP devices manufactured by Respironics, Res-med, Fisher Paykel and others, and Vapotherm high-flow technology devices. Various steam humidifiers and facial saunas are also known personal devices that are intended for short-term use.
Personal humidification devices of the types disclosed by U.S. Pat. No. 4,773,410 and manufactured by the OECO Corporation and Gulfstream are fairly large heavy machines and employ pumps to force humidified air through small bore tubing and simple nasal cannulas. These devices are uniquely capable of providing humidification effectively and efficiently to a sleeping subject. However, they often produce noise levels that may disturb the user and others nearby. In addition, the devices can be expensive to own and operate, and may require professional cleaning and maintenance.
Aerosol devices are small, portable and usually inexpensive. However, these devices employ sub-droplet liquid phase water (rather than the preferred gaseous or molecular phase water) which can transport viruses and bacteria to the user. In addition, the inhalation of nebulized water can cause broncho-spasm. These devices can be used to transport medication, but their uses for other treatment purposes have been questioned. Medically-supervised use may be advisable due to increased risk of broncho-spasm and potential for bacterial and/or viral inoculation, and therefore aerosol devices are not generally prescribed for personal humidification performed at the patient's home.
CPAP, BIPAP, high-flow, and blow-over technology devices tend to be light, quiet, portable and provide varying levels of humidification. However, these devices rarely provide 100 percent water-saturated air. In addition, few of these devices employ heated delivery and fewer employ monitored heated delivery. Generally, these devises use high-flow, fan-driven technologies that use large bore tubing and very uncomfortable and clumsy face masks or cannulas. While designed for sleep use, these devices tend to be the least comfortable and cannot compete for comfort with small-bore, heat-monitored pump-driven equipment. Consequently, many patients spend thousands of dollars on home equipment of this type only to discover that they dislike them causing compliance to prescribed use to be inconsistent at best.
Personal heated humidifiers such as steam humidifiers and facial saunas are well suited for humidifying an individual's airway. These devices are typically small, portable and relatively inexpensive. Unfortunately, these devices are generally limited to short-term use only. For example, these devices are typically designed for fifteen to thirty minutes of continuous use, and may require the user to bend over the device throughout this period of time. As with room humidifying steamers, other activities are nearly impossible while using personal humidifiers.
In addition to the above limitations, the previously described devices rarely provide oxygen-enriched air. Producing oxygen-enriched air that is simultaneously humidified has thus far been deemed uneconomical or impractical. However, there are medical conditions which would benefit from treatment with a humidified and oxygen-enriched air. Consequently, there is a demand for a device capable of providing such air, in addition to providing personal, convenient, and long-term use.
In view of the above, it can be appreciated that there are certain problems, shortcomings and disadvantages associated with the prior art, and that it would be desirable to develop an apparatus capable of providing an oxygen-enriched air having 100 percent gaseous water saturation to a patient.